1. Field of the Invention
The present invention relates to a storage battery and particularly to improvements therein to provide improved liquid tightness, wherein electrode leading-out members are disposed across the lateral wall of an electrolyte container body and an electrode bar leading to an electrode plate is connected to the surface of each electrode leading-out member facing the inside of the electrolyte container body.
2. Description of the Prior Art
The electrolyte container of a storage battery is composed basically of an electrolyte container body and a lid, and the lid is liquid-tightly fixed on the top of the electrolyte container body. Eelctrodes and an electrolytic solution are contained in the electrolyte container to constitute a battery, while the electrode leading-out members are usually upwardly led out through the lid, the portions through which the electrode leading-out members extend are liquid-tightly sealed.
In such a storage battery, it sometimes becomes necessary to lead out the electrode leading-out members laterally through the electrolyte container body depending upon the usage of the storage battery. Such storage battery with the electrode leading-out members laterally lead out not only facilitates the electrical connection in a particular use but also decreases the length of the conductor member required for leading out from the electrodes inside the electrolyte container, thus saving electrode material, improving the electrical characteristics and making the battery light in weight. On the other hand, since the portions of such electrode leading-out members extending through the lateral wall of the electrolyte container are in contact with the electrolytic solution, a more effective liquid tightness is required.
The lateral leading-out of the electrode leading-out members is conventionally carried out as follows.
A hole is formed in the lateral wall of the electrolyte container body and an electrode leading-out member made of lead is fitted in said hole and fixed therein by crimping. This method involves a number of processing steps and, moreover the dependability of the liquid tightness of the region where the electrode leading-out member extends through the lateral wall of the electrolytic container is low. In order to solve these problems, it is known to fill the clearance between the electrode leading-out member and the lateral wall of the electrolyte container but this further increases the number of processing steps, which is not desirable. In cases where the electrolyte container of a storage battery is made of a material of poor adhesive property, such as polypropylene, the effectiveness of an adhesive agent can hardly be expected.
Further, when an electrolyte container body with laterally led out electrode leading-out members is prepared, a different problem will arise in the subsequent step. More particularly, in a storage battery having electrode leading-out members lead out laterally through the electrolyte container body, the step of providing an connection between the electrode leading-out member and the electrode bar leading to the electrode plate becomes a problem if the electrolyte container body is made of thermoplastic synthetic resin. More particularly, the electrode leading-out member is embedded in the lateral wall of the electrolyte container body and the electrical connection between the electrode leading-out member and the electrode bar is made by welding, but the heat generated during welding cannot be overlooked. Thus, this heat influences the thermoplastic synthetic resin around the electrode leading-out member, deforming or even melting the same. This results in lessening the liquid-tight effect of the region where the electrode leading-out member extends through the lateral wall of the electrolyte container body.